Feat: introduced mutation and allow re-traversing of previous post-order

deferred_planarity_test/main.cpp

@@ -18,6 +18,9 @@ using namespace std;
 
 int compute_removed_edge_size(string input_file, vector<int> post_order);
 
+vector<int> generate_post_order(string input_file);
+vector<int> generate_mutated_post_order(string input_file, vector<int> post_order);
+
 int get_graph_size(string input_file) {
     ogdf::Graph G;
 
@@ -36,25 +39,23 @@ int get_graph_size(string input_file) {
 
 int main(int argc, char* argv[]) {
     string input_file = argv[1];
-    int num_runs = stoi(argv[2]);
-    // find the size of the graph here
-    int node_size = get_graph_size(input_file);
-    // generate order here
-    vector<int> post_order;
-    for (int i=0; i < node_size; ++i) {
-        post_order.push_back(i);
-    }
 
-    for (int i=0; i< num_runs; ++i) {
+    // generate order here
-        std::random_device rd;
+    vector<int> post_order = generate_post_order(input_file);
-        std::mt19937 g(rd());
+    std::copy(post_order.begin(), post_order.end(), std::ostream_iterator<int>(std::cout, " "));
-    
+    std::cout << std::endl;
-        std::shuffle(post_order.begin(), post_order.end(), g);
+
-        // print order
+    // generate mutated order
-        std::copy(post_order.begin(), post_order.end(), std::ostream_iterator<int>(std::cout, " "));
+    vector<int> mutated_order = generate_mutated_post_order(input_file, post_order);
-        std::cout << std::endl;
+    post_order = mutated_order;
-        std::cout << "Number of removed edges: " << compute_removed_edge_size(input_file, post_order) << std::endl;
+    std::copy(post_order.begin(), post_order.end(), std::ostream_iterator<int>(std::cout, " "));
-    }
+    std::cout << std::endl;
+
+
+    // print order
+    int removed_edges = compute_removed_edge_size(input_file, post_order);
+    std::cout << "Number of removed edges: " << removed_edges << std::endl;
+
 
 	return 0;
 }

deferred_planarity_test/mps.cpp

@@ -20,7 +20,7 @@ maximal_planar_subgraph_finder::get_new_node(node_type t) {
 }
 
 //Determine the post-order-list by a DFS-traversal.
-void 
+vector<int> 
 maximal_planar_subgraph_finder::postOrderTraversal() {
 	node::init_mark();
 	int postOrderID = 0;
@@ -29,8 +29,113 @@ maximal_planar_subgraph_finder::postOrderTraversal() {
 			_node_list[i]->DFS_visit(_post_order_list, postOrderID);
 		}
 	}
+
+    vector<int> post_order;
+    for (int i = 0; i < _post_order_list.size(); ++i) {
+        post_order.push_back(_post_order_list[i]->node_id());
+    }
+    return post_order;
 }
 
+
+//Determine the post-order-list by a DFS-traversal.
+void 
+maximal_planar_subgraph_finder::guidedPostOrderTraversal(vector<int> post_order) {
+	node::init_mark();
+
+    vector<int> rev_post_order;
+    for (int i = post_order.size() - 1; i >= 0; --i) {
+        rev_post_order.push_back(post_order[i]);
+    }
+	int postOrderID = 0;
+
+    int end_condition = _node_list.size();
+    int start = rev_post_order[0];
+    int i = start;
+    while (true)
+    {
+        if (((start > 0) && (i == (start - 1))) || ((start == 0 ) && (i == end_condition - 1)))
+        {
+            if (!_node_list[i]->is_marked())
+            {
+                _node_list[i]->guided_DFS_visit(_post_order_list, _node_list, postOrderID, rev_post_order);
+            }
+            break;
+        }
+        // std::cout << _node_list[i]->node_id() << ", " << !_node_list[i]->is_marked() << std::endl;
+        if (!_node_list[i]->is_marked())
+        {
+            _node_list[i]->guided_DFS_visit(_post_order_list, _node_list, postOrderID, rev_post_order);
+        }
+        i = (i + 1) % end_condition;
+    }
+}
+
+//Determine the post-order-list by a DFS-traversal.
+vector<int> 
+maximal_planar_subgraph_finder::mutatedPostOrderTraversal(vector<int> post_order) {
+	node::init_mark();
+
+    vector<int> rev_post_order;
+    for (int i = post_order.size() - 1; i >= 0; --i) {
+        rev_post_order.push_back(post_order[i]);
+    }
+	int postOrderID = 0;
+
+    // introduce random selection
+    std::random_device rd;
+    std::mt19937 rng(rd());
+    // Define the range [0, n]
+    int n = _node_list.size() - 1;  // Change 'n' to your desired upper bound
+    // Create a uniform distribution for the range [0, n]
+    std::uniform_int_distribution<int> distribution(0, n);
+    // Generate a random number between 0 and n (inclusive)
+    int mutate_point = distribution(rng);
+    std::cout << "the mutate point: " << mutate_point << std::endl;
+
+    // set loop variables
+    int start = rev_post_order[0];
+    int i = start;
+
+    // if mutate_point = 0
+    if (mutate_point == 0) {
+        // generate another point
+        start = distribution(rng); 
+    }
+
+
+    int end_condition = _node_list.size();
+    while (true)
+    {
+        if (((start > 0) && (i == (start - 1))) || ((start == 0 ) && (i == end_condition - 1)))
+        {
+            if (!_node_list[i]->is_marked())
+            {
+                _node_list[i]->mutated_DFS_visit(_post_order_list, _node_list, postOrderID, rev_post_order, mutate_point);
+            }
+            break;
+        }
+        // std::cout << _node_list[i]->node_id() << ", " << !_node_list[i]->is_marked() << std::endl;
+        if (!_node_list[i]->is_marked())
+        {
+            _node_list[i]->mutated_DFS_visit(_post_order_list, _node_list, postOrderID, rev_post_order, mutate_point);
+        }
+        i = (i + 1) % end_condition;
+    }
+
+    vector<int> return_order;
+    for (int i = 0; i < _post_order_list.size(); ++i) {
+        return_order.push_back(_post_order_list[i]->node_id());
+    }
+
+    // we have to reverse the order as we add to list in the forward direction of recursion
+    // unlike that of previous methods where we add to list in the return direction of recursion
+    std::reverse(return_order.begin(), return_order.end());
+    return return_order;
+}
+
+
+
 //Set the post-order-list via given list
 void
 maximal_planar_subgraph_finder::set_post_order(vector<int> post_order) {

deferred_planarity_test/mps.h

@@ -10,6 +10,9 @@
 #include <vector>
 #include <utility>
 #include <climits>
+#include <random>
+#include <algorithm>
+#include <unordered_set>
 
 using namespace std;
 
@@ -53,6 +56,8 @@ public:
 	node* adj(int i);
 	void set_adj_list(vector<node*> vec);
 	void DFS_visit(vector<node*> &dfsList, int &index);
+	void guided_DFS_visit(vector<node*> &dfsList, vector<node*> &node_list, int &index, vector<int> rev_post_order);
+	void mutated_DFS_visit(vector<node*> &dfsList, vector<node*> &node_list, int &index, vector<int> rev_post_order, int &mutate_point);
 
 	//PARENT-CHILDREN
 	void set_parent(node* n) ;
@@ -143,10 +148,14 @@ public:
 	~maximal_planar_subgraph_finder();
 	int find_mps(string input_file);
 	int compute_removed_edge_size(string input_file, vector<int> post_order);
+	vector<int> generate_post_order(string input_file);
+	vector<int> generate_mutated_post_order(string input_file, vector<int> post_order);
 	node* get_new_node(node_type t);
     void read_from_gml(string input_file);
 	int output_removed_edge_size();
-	void postOrderTraversal();
+	vector<int> postOrderTraversal();
+	vector<int> mutatedPostOrderTraversal(vector<int> post_order);
+	void guidedPostOrderTraversal(vector<int> post_order);
     void set_post_order(vector<int> post_order);
 	void sort_adj_list();
 	void determine_edges();

deferred_planarity_test/mps_test.cpp

@@ -8,6 +8,9 @@
 //-----------------------------------------------------------------------------------
 // Finding MPS
 //-----------------------------------------------------------------------------------
+
+// programs to call from main:
+
 int find_mps(string input_file) {
 	maximal_planar_subgraph_finder m;
 	return m.find_mps(input_file);
@@ -18,6 +21,19 @@ int compute_removed_edge_size(string input_file, vector<int> post_order) {
     return m.compute_removed_edge_size(input_file, post_order);
 }
 
+vector<int> generate_post_order(string input_file) {
+    maximal_planar_subgraph_finder m;
+    return m.generate_post_order(input_file);
+}
+
+vector<int> generate_mutated_post_order(string input_file, vector<int> post_order) {
+    maximal_planar_subgraph_finder m;
+    return m.generate_mutated_post_order(input_file, post_order);
+}
+
+
+// ---------
+
 int maximal_planar_subgraph_finder::find_mps(string input_file) {
 	read_from_gml(input_file);
 	postOrderTraversal();
@@ -27,10 +43,34 @@ int maximal_planar_subgraph_finder::find_mps(string input_file) {
 	return output_removed_edge_size();
 }
 
+vector<int> maximal_planar_subgraph_finder::generate_post_order(string input_file) {
+    read_from_gml(input_file);
+    return postOrderTraversal();
+}
+
+vector<int> maximal_planar_subgraph_finder::generate_mutated_post_order(string input_file, vector<int> post_order) {
+    read_from_gml(input_file);
+    return mutatedPostOrderTraversal(post_order);
+}
+
 
 int maximal_planar_subgraph_finder::compute_removed_edge_size(string input_file, vector<int> post_order) {
 	read_from_gml(input_file);
-    set_post_order(post_order);
+    guidedPostOrderTraversal(post_order);
+
+    // let's reverse the order
+    std::reverse(_post_order_list.begin(), _post_order_list.end());
+    // then set post_order_index
+    for (int i = 0; i < _post_order_list.size(); ++i) {
+        _node_list[_post_order_list[i]->node_id()]->set_post_order_index(i);
+    }
+
+    std::cout << "check order of duplicated traversal" << std::endl;
+    for (int i = 0; i < _post_order_list.size(); ++i) {
+        std::cout << _post_order_list[i]->node_id() << " ";
+    }
+
+    std::cout << std::endl;
 	sort_adj_list();
 	determine_edges();
 	back_edge_traversal();

deferred_planarity_test/node.cpp

@@ -66,6 +66,103 @@ void node::DFS_visit(vector<node*> &dfsList, int &index) {
 	++index;
 }
 
+
+void node::guided_DFS_visit(vector<node*> &dfsList, vector<node*> &node_list, int &index, vector<int> rev_post_order) {
+	mark();
+    // you will want to sort the neighbor nodes by the order they appear in the rev_post_order
+    vector<node *> neighbor_list;
+    std::unordered_set<int> neighbor_set; 
+    
+    // create an unordered set to efficiently check for presence of an element
+    for (int i = 0; i < _adj_list.size(); ++i) {
+        neighbor_set.insert(_adj_list[i]->node_id());
+    }
+
+    // when an element in rev_post_order is found in neighbor_set, we add that to neighbor_list
+    for (int i = 0; i < rev_post_order.size(); ++i) {
+        if (neighbor_set.find(rev_post_order[i]) != neighbor_set.end()) {
+            neighbor_list.push_back(node_list[rev_post_order[i]]);
+        }
+    }
+
+    // print the neighbors
+    // std::cout << "current index: " << this->node_id() << std::endl;
+    // for (int i = 0; i < neighbor_list.size(); ++i) {
+    //     std::cout << neighbor_list[i]->node_id() << " ";
+    // }
+    // std::cout << std::endl;
+
+	set_post_order_index(index);
+	dfsList.push_back(this);
+	++index;
+
+	for (int i = 0; i < neighbor_list.size(); ++i) {
+		if (!neighbor_list[i]->is_marked()) {
+			neighbor_list[i]->_parent = this;
+			neighbor_list[i]->guided_DFS_visit(dfsList, node_list, index, rev_post_order);
+		}
+	}
+}
+
+
+void node::mutated_DFS_visit(vector<node*> &dfsList, vector<node*> &node_list, int &index, vector<int> rev_post_order, int &mutate_point) {
+	mark();
+    // you will want to sort the neighbor nodes by the order they appear in the rev_post_order
+    vector<node *> neighbor_list;
+    std::unordered_set<int> neighbor_set; 
+    
+    // create an unordered set to efficiently check for presence of an element
+    for (int i = 0; i < _adj_list.size(); ++i) {
+        neighbor_set.insert(_adj_list[i]->node_id());
+    }
+
+    // when an element in rev_post_order is found in neighbor_set, we add that to neighbor_list
+    for (int i = 0; i < rev_post_order.size(); ++i) {
+        if (neighbor_set.find(rev_post_order[i]) != neighbor_set.end()) {
+            neighbor_list.push_back(node_list[rev_post_order[i]]);
+        }
+    }
+
+    // print the neighbors
+    std::cout << "current index: " << this->node_id() << std::endl;
+    for (int i = 0; i < neighbor_list.size(); ++i) {
+        std::cout << neighbor_list[i]->node_id() << " ";
+    }
+    std::cout << std::endl;
+
+	set_post_order_index(index);
+	dfsList.push_back(this);
+	++index;
+
+    if (index - 1 == mutate_point) {
+        // Create a random number generator and seed it
+        std::cout << "mutated at index: " << index - 1<< "and at mutate point: " << mutate_point << std::endl;
+        std::random_device rd;
+        std::mt19937 rng(rd());
+        // Use std::shuffle to shuffle the elements in the vector
+        std::shuffle(neighbor_list.begin(), neighbor_list.end(), rng);
+        // print the neighbors
+        std::cout << "order after mutation: " << std::endl;
+        std::cout << "current index: " << this->node_id() << std::endl;
+        for (int i = 0; i < neighbor_list.size(); ++i)
+        {
+            std::cout << neighbor_list[i]->node_id() << " ";
+        }
+        std::cout << std::endl;
+    } 
+    
+    for (int i = 0; i < neighbor_list.size(); ++i)
+    {
+        if (!neighbor_list[i]->is_marked())
+        {
+            neighbor_list[i]->_parent = this;
+            neighbor_list[i]->mutated_DFS_visit(dfsList, node_list, index, rev_post_order, mutate_point);
+        }
+    }
+}
+
+
+
 //-----------------------------------------------------------------------------------
 // PARENT-CHILDREN
 //-----------------------------------------------------------------------------------